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101.
On the evolution and diversification of an Andean clade of reptiles: combining morphology and DNA sequences of the palluma group (Liolaemidae: Phymaturus)
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Fernando Lobo Diego A. Barrasso Thomas Hibbard Néstor G. Basso 《Zoological Journal of the Linnean Society》2016,176(3):648-673
Phymaturus comprises 44 species mainly distributed along the south‐west of South America on both sides of the Andes. In this study we present a phylogenetic analysis of Phymaturus of the palluma group, one of its two large clades, including almost all described species. This analysis duplicates the number of in‐group taxa compared with previous contributions. We performed a total‐evidence analysis, combining molecular and morphological characters: sequencing fragments of cytochome b (cytb), 12S, and ND4, for all terminals; describing 45 new morphological characters; and incorporating all DNA sequences available from GenBank. Separate analyses of morphology and DNA partitions are presented and discussed in detail. Seven subclades are recognized here. We named three new subclades and redefined another, found to be paraphyletic. In order to recognize lineages within the traditional Phymaturus palluma group we proposed to treat it as a natural group, containing within it the ranks of clade, subclade, and lineages, respectively. The palluma group is composed by the vociferator and the bibronii clades. The vociferator clade, composed of Chilean and Argentinean species, would be the most basal in the group. Within the bibronii clade, the roigorum subclade includes the Phymaturus verdugo lineage, whereas the mallimaccii subclade would consist of 13 terminal taxa, for which three Chilean species have been added. In this study, morphological apomorphies are identified for all clades and the evolution of ‘male head melanism’ is discussed. © 2015 The Linnean Society of London 相似文献
102.
Enilson B. Silva Felipe G. Fonseca Luís R. F. Alleoni Sandra S. Nascimento Paulo H. Grazziotti Bárbara O. Nardis 《International journal of phytoremediation》2016,18(9):847-852
It is important to know the mechanisms for forage development, especially those related to the tolerance of potentially toxic elements, when considering their use in phytoremediation in heavy metal contaminated areas. In this study, we evaluated plant growth, concentration, and the availability of cadmium (Cd) for forage grasses (Panicum maximum Jacq. cv. Aruana and cv. Tanzânia; Brachiaria decumbens cv. Basilisk; Brachiaria brizantha cv. Xaraés and cv. Marandu) cultivated in Cd contaminated soils. The experiments were performed under greenhouse conditions over a 90-day evaluation period, and the Cd rates were 2, 4, and 12 mg/kg of soil. The relative growth rate of the forage grasses decreased as Cd rates increased, and the following descending order of susceptibility was observed: Marandu > Xaraés > Aruana > Tanzânia > Basilisk, with regard to phytotoxicity in these plants. The forage Cd concentration increased in line with increases in the Cd rates. Cd contents extracted by Mehlich-1 and by diethylenetriaminepentaacetic acid presented high positive correlation with forage relative growth. The forage plants did not block Cd entry into the food chain because they were not capable of limiting Cd absorption. 相似文献
103.
目的:比较阴式全子宫切除术与腹腔镜下全子宫切除术的临床治疗效果。方法:回顾性分析2014年6月-2015年6月我院收治的137例子宫良性病变患者的临床病历资料,按照手术方式将其分为阴式组(行阴式全子宫切除术)和腹腔镜组(行腹腔镜下全子宫切除术),比较两组患者的术中、术后临床指标及术后并发症情况。结果:阴式组手术时间及术中出血量均少于腹腔镜组,差异有统计学意义(P0.05)。阴式组肛门排气时间、下床活动时间以及住院时间均短于腹腔镜组,住院总费用低于腹腔镜组,差异有统计学意义(P0.05)。两组患者并发症发生情况差异无统计学意义(P0.05)。结论:阴式全子宫切除术较腹腔镜下全子宫切除术而言,具有手术创伤小、术后恢复快的特点,值得临床推广。 相似文献
104.
Anton A. Buzdin Alina V. Artcibasova Natalya F. Fedorova Maria V. Suntsova Andrew V. Garazha Maxim I. Sorokin 《Cell cycle (Georgetown, Tex.)》2016,15(24):3378-3389
Responses to human cytomegalovirus (HCMV) infection are largely individual and cell type specific. We investigated molecular profiles in 2 primary cell cultures of human fibroblasts, which are highly or marginally sensitive to HCMV infection, respectively. We screened expression of genes and microRNAs (miRs) at the early (3 hours) stage of infection. To assess molecular pathway activation profiles, we applied bioinformatic algorithms OncoFinder and MiRImpact. In both cell types, pathway regulation properties at mRNA and miR levels were markedly different. Surprisingly, in the infected highly sensitive cells, we observed a “freeze” of miR expression profiles compared to uninfected controls. Our results evidence that in the sensitive cells, HCMV blocks intracellular regulation of microRNA expression already at the earliest stage of infection. These data suggest somewhat new functions for HCMV products and demonstrate dependence of miR expression arrest on the host-encoded factors. 相似文献
105.
Guðmundur J. Óskarsson Asta Gudmundsdottir Sveinn Sveinbjörnsson Þorsteinn Sigurðsson 《Marine Biology Research》2016,12(1):16-29
The Northeast Atlantic mackerel (Scomber scombrus) has been extending its summer feeding distribution north and west, including around Iceland, since around 2006. The objective of this study is to quantify the weight gain and total food consumption of mackerel and to evaluate the food competition between mackerel and herring (Clupea harengus) feeding in the marine ecosystem around Iceland during the summers 2009–2011. Mackerel feeding in Icelandic waters gained around 43% on average in weight during these summers. Based on swept-area abundance estimates of mackerel from an international survey in 2011 and available estimates of food conversion efficiency in mackerel, the weight gain in Icelandic waters in 2011 corresponded to a total consumption of around 3.4 (2.4?4.5) million tonnes. Overall, 98% of 2314 mackerel, 91% of 398 Icelandic summer-spawning herring and 96% of 424 Norwegian spring-spawning herring stomachs, collected over the summers 2009?2011, contained food. The mean weight of the stomach content of mackerel was higher than for herring in all the years. While the stomach content weight of mackerel was generally highest in southeastern and southwestern areas, it was highest for herring in western, eastern and northern areas. Analysis of stomach contents showed that Copepoda were the most important food of mackerel in most areas, while Copepoda and Euphausiacea were the most important food items for herring. Fish prey contributed a higher proportion in stomachs of mackerel than herring, although relatively low for both species. 相似文献
106.
Yuki Takayasu Yusuke Ogura Ryo Towada 《Bioscience, biotechnology, and biochemistry》2016,80(8):1459-1463
The first synthesis of the (9R,13R)-stereoisomer of LDS1, a flower-inducing oxylipin isolated from Lemna paucicostata, has been achieved from a known allylic alcohol by a seven-step sequence that involves the Horner–Wadsworth–Emmons olefination to construct its full carbon framework and an enzymatic hydrolysis of a penultimate methyl ester intermediate to provide the target molecule. 相似文献
107.
该研究以冷饭团果实为材料,用甘油、淀粉、明胶、琼脂、焦亚硫酸钠按不同比例配制成3种保鲜剂处理冷饭团果实,放在平均温度11℃、平均湿度85%的冰箱保鲜层保鲜;用壳聚糖配制成4种不同质量分数浓度的保鲜剂处理冷饭团果实,放在平均温度11℃、平均湿度85%的冰箱保鲜层保鲜;用真空和臭氧装置保鲜处理,放在平均温度15℃、平均湿度40%的屋中,共4种保鲜方法对冷饭团果实进行保鲜处理.通过测定冷饭团果实的失重率、可溶性固形物的含量以及抗坏血酸(Vc)含量的变化来判断各种保鲜的效果,探索出最好的保鲜方法.结果表明:4种保鲜方法均能明显降低冷饭团果实的失重率,延缓可溶性固形物和Vc含量的降低速率;两类保鲜剂中,以甘油3 g、淀粉4 g、明胶1.5 g、琼脂1 g、焦亚硫酸钠1.5 g混合,用蒸馏水配制成500 mL保鲜剂的保鲜效果最好;真空和臭氧对冷饭团果实的保鲜中,真空的保鲜效果比臭氧好. 相似文献
108.
M. Woiczinski A. Steinbrück P. Weber P. E. Müller V. Jansson Ch. Schröder 《Computer methods in biomechanics and biomedical engineering》2016,19(10):1033-1045
Total knee arthroplasty (TKA) is a successful procedure for osteoarthritis. However, some patients (19%) do have pain after surgery. A finite element model was developed based on boundary conditions of a knee rig. A 3D-model of an anatomical full leg was generated from magnetic resonance image data and a total knee prosthesis was implanted without patella resurfacing. In the finite element model, a restarting procedure was programmed in order to hold the ground reaction force constant with an adapted quadriceps muscle force during a squat from 20° to 105° of flexion. Knee rig experimental data were used to validate the numerical model in the patellofemoral and femorotibial joint. Furthermore, sensitivity analyses of Young’s modulus of the patella cartilage, posterior cruciate ligament (PCL) stiffness, and patella tendon origin were performed. Pearson’s correlations for retropatellar contact area, pressure, patella flexion, and femorotibial ap-movement were near to 1. Lowest root mean square error for retropatellar pressure, patella flexion, and femorotibial ap-movement were found for the baseline model setup with Young’s modulus of 5 MPa for patella cartilage, a downscaled PCL stiffness of 25% compared to the literature given value and an anatomical origin of the patella tendon. The results of the conducted finite element model are comparable with the experimental results. Therefore, the finite element model developed in this study can be used for further clinical investigations and will help to better understand the clinical aspects after TKA with an unresurfaced patella. 相似文献
109.
Magdalena Jakubowska Monika Normant-Saremba 《Marine and Freshwater Behaviour and Physiology》2016,49(3):173-185
The aim of this study was to investigate the effect of CO2-induced water acidification (pH values: 8.1 ? control, 7.5 and 7.0) on the hemolymph osmolality and total metabolic rate of amphipod Gammarus oceanicus under short-term exposure. The hemolymph osmolality was measured using a vapor pressure osmometer. The metabolic rate was determined based on the heat dissipation measurements using a Calvet-type isothermal twin calorimeter. The hemolymph osmolality remained unchanged after exposure to pH 7.5 and it increased in the lowest treatment. Acidification did not significantly affect the resting or active metabolic rate. The observed results indicate that high osmolality maintained during hypercapnia did not generate additional physiological costs. It may therefore be concluded that the studied species is preadapted for this factor. The long-term adaptation to hypoosmotic conditions in the brackish Baltic Sea might also have preadapted it to hypercapnia because similar physiological mechanisms are responsible for the resistance to both factors. 相似文献
110.
The importance of phenolic compounds for responding to various environmental conditions has been widely emphasized. However, the role of interactions between polyphenols and ecological factors, especially C, N, and P stoichiometry was little studied. Here, 15 sites across five provinces of Pinus bungeana in temperate regions of China were studied. The results showed that the higher values of total phenolic contents (TPC) of leaf and litter were distributed among the north distribution area of P. bungeana, lower values were in the south, whereas soil TPC were contrary to leaf and litter TPC. The stepwise regression, path analysis and decision index of path analysis for leaf TPC and ecological factors showed that altitude had the most direct impact on leaf TPC. Moreover, the principal determinants of leaf, litter and soil TPC were soil C/P ratios, longitude, and soil N/P ratios, respectively. In addition, the leaf, litter and soil TPC of P. bungeana were limited by soil C/N ratios, mean annual temperature, and soil P, respectively. Overall, our study provided evidence that ecological factors affected strongly the leaf, litter and soil TPC of P. bungeana. 相似文献